ANATOMY AND AFFINITY OF CERTAIN RARE AND PRIMITIVE FERNS. 377 
apparent tendencies an increase in the number of subjects of comparison is of 
material help towards a balanced conclusion. The sporangial condition in the 
“ Acrostichoid ” Cryptogramme crispa, R. Br. — with which Llavea has been 
associated by the systematists — is, then, of special interest. The salient features of 
sporangial-form in his plant are shown in Plates V and VI. The stalk is short and of 
variable construction. In its simplest condition it is three rowed (figs. 48, 51, 57), 
Text-fig. 13. 
Text-fig. 14 
but four, five, and six rows have been found (figs. 49, 52, 53). The annulus is 
typically oblique, and passes close to the stalk (figs. 48, 53, 55). Irregularities are 
not uncommon (figs. 54, 57). In some cases the annulus does not reach the stalk 
(fig. 50), in others it both reaches the stalk and is interrupted by it (figs. 51, 52). 
The spore-counts made are 45, 46, 48, 50, 51, 52. The typical spore-number is 52. 
I am much indebted to Professor Bower for figures drawn by him from sporangia 
of Cryptogramme. On these my figures are founded. 
The figures detailed strengthen the impression that in the genera under discussion 
